PHILADELPHIA -- Bryce Harper stood in front of a microphone on a beautiful Sunday afternoon at Citizens Bank Park and addressed the 29,336 fans who came to see the Phillies play their final regular-season home game in 2021.

He thanked them, then told them that he hoped to see them again on Oct. 11.

Oct. 11 is Game 3 of the National League Division Series. The Phillies will need to win the National League East to get there, but those chances took a significant hit with a 6-0 loss to the Pirates. It snapped the Phillies’ five-game winning streak and dropped them 2 1/2 games behind the Braves with only six to play after Atlanta held on for a 4-3 win in San Diego.

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Sunday’s loss means the Phillies (81-75) probably need to sweep the Braves (83-72) this week in Atlanta to give them any realistic hopes of capturing their first NL East title since 2011. The Braves’ magic number is at five, which means any combination of five Braves wins and Phillies losses clinches Atlanta’s fourth consecutive NL East title.

“I mean, every time you play somebody, you want to sweep them,” Harper said. “We'd be up half a game or something like that, if we went in there and swept. We haven't played Miami very well the last couple years, especially this year as well, so yeah, I would imagine a sweep would be nice.

“But as a team, as a whole, I think we’re confident going into Atlanta. We have to go down there, we have to do our job, we have to be ready to go from Pitch 1, get 27 outs a game, and we have to be very good with all 27 of those outs.”

The Phillies started rookie Hans Crouse on Sunday. They acquired him from Texas on July 30 in the trade that brought them Kyle Gibson and Ian Kennedy. Sunday morning’s announcement that Crouse would start surprised a few people because it meant he would make his big league debut in the Phillies’ most important home game since 2011, despite having started only one game above Double-A in his career.

Crouse learned he would start about 90 minutes after Saturday’s game.

“Definitely was nervous for sure,” he said “The biggest thing was I just wanted to embrace all the emotions I felt out there today. I knew I was going to feel anxious and nervous but trying to use that to my advantage and go out there and just throw the game I know how.”

Crouse allowed a first-pitch home run off the right-field foul pole to Cole Tucker to start the game. Crouse was just the eighth pitcher in Phillies history to allow a home run to the first batter he faced, according to Baseball Almanac.

“I just said to myself, ‘Well, that’s one way to start a career,’” Crouse said. “It is what it is. I’m happy with how I composed myself and how I got two quick outs after that and got into a rhythm in a game.”

Crouse did not allow another run in three innings. Cristopher Sánchez pitched two scoreless innings in relief. But the Phillies managed just six hits, including four against Pirates rookie Max Kranick, who started the day with a 7.28 ERA.

José Alvarado allowed two runs in the seventh and Adonis Medina allowed two runs in the eighth. Medina pitched with a 3-0 deficit because Ian Kennedy and Sam Coonrod were unavailable, making Héctor Neris Sunday’s closer.

The Phillies needed to be better on Sunday, but it could be worse. Back on Sept. 10, following a bad loss to Colorado, the Phillies were 4 1/2 games behind the Braves with 21 games to play. Harper said then that he just wanted the Phillies to be within striking distance when they played them in Atlanta.

Well, here they are.

“Of course, we want to be better,” Harper said. “Of course, we wanted to sweep this whole homestand. We weren't able to do that, so we have to put this behind us and get ready to go in Atlanta. We are within the striking distance that I talked about, and as a team, we believe that going down there, playing our game, they have their three guys going, we have our three guys going, and it's going to be a great series. … I'm excited as an individual to go down there and play. I'm ready to go, and I think all of us as a team are ready to go.”